systemd-import-generator - Generator for automatically downloading disk images at boot

systemd-import-generator supports the system credentials logic. The following credentials are used when
       passed in:

       import.pull
           This credential should be a text file, with each line referencing one download operation. Each line
           should follow the same format as the value of the systemd.pull= kernel command line option described
           above.

           Added in version 257.

systemd-import-generator may be used to automatically download disk images (tarballs or DDIs) via
       systemd-importd.service(8) at boot, based on parameters on the kernel command line or via system
       credentials. This is useful for automatically deploying an systemd-confext(8), systemd-sysext(8),
       systemd-nspawn(1)/ systemd-vmspawn(1) or systemd-portabled.service(8) image at boot. This provides
       functionality equivalent to importctl(1), but accessible via the kernel command line and system
       credentials.

       systemd-import-generator implements systemd.generator(7).

Example1.DownloadConfigurationExtension

           systemd.pull=raw,confext::https://example.com/myconfext.raw.gz

       With a kernel command line option like the above a configuration extension DDI is downloaded
       automatically at boot from the specified URL, validated cryptographically, uncompressed and installed.

       Example2.DownloadSystemExtension(WithoutValidation)

           systemd.pull=tar,sysext,verify=no::https://example.com/mysysext.tar.gz

       With a kernel command line option like the above a system extension tarball is downloaded automatically
       at boot from the specified URL, uncompressed and installed – without any cryptographic validation. This
       is useful for development purposes in virtual machines and containers. Warning: do not deploy a system
       with validation disabled like this!

       systemd-import-generator understands the following kernel-command-line(7) parameters:

       systemd.pull=
           This option takes a colon separate triplet of option string, local target image name and remote URL.
           The local target image name can be specified as an empty string, in which case the name is derived
           from the specified remote URL. The remote URL must using the "http://", "https://", "file://"
           schemes. The option string itself is a comma separated list of options:

           rw, ro
               Controls whether to mark the local image as read-only. If not specified read-only defaults to
               off.

               Added in version 257.

           verify=
               Controls whether to cryptographically validate the download before installing it in place. Takes
               one of "no", "checksum", or "signature" (the default if not specified). For details see the
               --verify= of importctl(1).

               Added in version 257.

           sysext, confext, machine, portable
               Controls the image class to download, and thus ultimately the target directory for the image,
               depending on this choice the target directory /var/lib/extensions/, /var/lib/confexts/,
               /var/lib/machines/ or /var/lib/portables/ is selected.

               Specification of exactly one of these options is mandatory.

               Added in version 257.

           tar, raw
               Controls the type of resource to download, i.e. a (possibly compressed) tarball that needs to be
               unpacked into a file system tree, or (possibly compressed) raw disk image (DDI).

               Specification of exactly one of these options is mandatory.

               Added in version 257.

           Added in version 257.

       systemd.pull.success_action=, systemd.pull.failure_action=
           Controls whether to execute an action such as reboot, power-off and similar after completing the
           download successfully, or unsuccessfully. See SuccessAction=/FailureAction= on systemd.unit(5) for
           details about the available actions. If not specified, no action is taken, and the system will
           continue to boot normally.

           Added in version 257.

       systemd-import-generator - Generator for automatically downloading disk images at boot

systemd(1), systemd-importd.service(8), kernel-command-line(7), systemd.system-credentials(7),
       importctl(1)

systemd 257.7                                                                        SYSTEMD-IMPORT-GENERATOR(8)

       /usr/lib/systemd/system-generators/systemd-import-generator